Wheelchair lift device

Abstract

The present invention is directed to a wheelchair lift device, more particularly, to a folding wheelchair lift device that is independently operable by a wheelchair user without the wheelchair user exiting their chair. The wheelchair lift apparatus, in various embodiments, may include a linkage frame having a nesting linkage geometry; linkage frame components with alignment and locking features; an extension handle having alignment and locking features; and an adjustable telescopic axle-rest assembly having alignment and locking features.

The invention claimed is: 
     
       1. A wheelchair lift device comprising:
 a linkage assembly having a parallel-bar-linkage architecture, wherein at least two parallel links of the parallel-bar-linkage architecture are moveable with respect to one another; and 
 an extension handle in operable connection with the linkage assembly; 
 wherein the linkage assembly and extension handle are configured to allow a wheelchair user to independently operate the wheelchair lift device while remaining seated in the wheelchair; and 
 wherein the extension handle is capable of actuating a lifting of the wheelchair while the user remains seated in the wheelchair when the user operates, applies force to, pulls on, pushes on, or engages the extension handle. 
 
     
     
       2. The wheelchair lift device of  claim 1 , wherein the linkage assembly further comprises an axle-rest assembly configured to provide for alignment and locking of the wheelchair lift device. 
     
     
       3. The wheelchair lift device of  claim 1 , wherein the linkage assembly comprises one or more linkage components configured to provide for alignment and locking of the wheelchair lift device. 
     
     
       4. A wheelchair lift device comprising:
 two pairs of parallel links capable of moving with respect to one another due to a third link located between a first end of the two pairs of parallel links; 
 an extension handle connected to a second end of the two pairs of parallel links, wherein said extension handle includes one or more apparatus connected on one end to the two pairs of parallel links and on a second end to the extension handle for actuation of the wheelchair lift device. 
 
     
     
       5. The wheelchair lift device of  claim 4 , wherein the two pairs of parallel links that move with respect to one another remain parallel with each other during movement. 
     
     
       6. The wheelchair lift device of  claim 4 , wherein a force that causes of at least one of the two pairs of parallel links to move lifts a telescopic axle-rest assembly. 
     
     
       7. The wheelchair lift device of  claim 6 , wherein the telescopic axle-rest assembly comprises a structure capable of accommodating an axle of a wheelchair. 
     
     
       8. A wheelchair lift device comprising:
 a parallel-bar-linkage architecture comprising:
 four pairs of linkage members; and 
 an extension handle and telescopic axle-rest assembly each in operable connection with the parallel-bar-linkage architecture; 
 
 wherein the wheelchair lift device is configured such that during use, force applied to the extension handle by a user is transferred through the extension handle and the parallel-bar-linkage architecture to cause lifting of the telescopic axle-rest assembly; 
 wherein the wheelchair lift device is further configured such that two of the four pairs of linkage members are caused to rotate when force is applied to the extension handle; 
 wherein the two pairs of linkage members that are caused to rotate comprise a first pair and a second pair, wherein the second pair has a length that is longer than a length of the first pair; and 
 wherein each member of the second pair comprises an S-shaped bend. 
 
     
     
       9. A wheelchair lift device comprising:
 a parallel-bar-linkage architecture comprising:
 four pairs of linkage members; and 
 an extension handle and telescopic axle-rest assembly each in operable connection with the parallel-bar-linkage architecture; 
 
 wherein the wheelchair lift device is configured such that during use, force applied to the extension handle by a user is transferred through the extension handle and the parallel-bar-linkage architecture to cause lifting of the telescopic axle-rest assembly; 
 wherein the wheelchair lift device is further configured such that two of the four pairs of linkage members are caused to rotate when force is applied to the extension handle; 
 wherein the two pairs of linkage members that are caused to rotate comprise a first pair and a second pair, wherein the second pair has a length that is longer than a length of the first pair; 
 wherein each member of the second pair comprises an S-shaped bend; and 
 wherein one of the four pairs of linkage members comprises a groove which is sized to accommodate the S-shaped bend when the wheelchair lift device is folded in a closed position. 
 
     
     
       10. A wheelchair lift device comprising:
 a parallel-bar-linkage architecture comprising:
 four pairs of linkage members; and 
 an extension handle and telescopic axle-rest assembly each in operable connection with the parallel-bar-linkage architecture; 
 
 wherein the wheelchair lift device is configured such that during use, force applied to the extension handle by a user is transferred through the extension handle and the parallel-bar-linkage architecture to cause lifting of the telescopic axle-rest assembly; wherein the extension handle comprises:
 a pair of elongated grip members; and 
 a structure comprising one or more slots; and 
 
 wherein the structure comprising one or more slots bridges the pair of elongated grip members.